https://www.cnblogs.com/rocketfan/p/4976806.html
https://www.tensorflow.org/tutorials/word2vec
https://www.jianshu.com/p/f682066f0586
【Word2Vec相关链接】https://www.youtube.com/watch?v=D-ekE-Wlcds
TensorFlow的NCE-Loss的实现和word2vec
http://www.jianshu.com/p/fab82fa53e16
